Map() constructor

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The Map() constructor creates Map objects.

Syntax

js
new Map()
new Map(iterable)

Note: Map() can only be constructed with new. Attempting to call it without new throws a TypeError.

Parameters

iterable Optional

An Array or other iterable object whose elements are key-value pairs. (For example, arrays with two elements, such as [[ 1, 'one' ],[ 2, 'two' ]].) Each key-value pair is added to the new Map.

Examples

Creating a new Map

js
const myMap = new Map([
  [1, "one"],
  [2, "two"],
  [3, "three"],
]);

Specifications

Specification
ECMAScript Language Specification
# sec-map-constructor

Browser compatibility

Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
Deno
Node.js
Map() constructor
new Map(iterable)
new Map(null)

See also